There are a few zero pipe mini-splits. They hang across the window frame and use 1 inch of height with an inside bidirectional radiator and an external one, SCr

There are a few zero pipe mini-splits. They hang across the window frame and use 1 inch of height with an inside bidirectional radiator and an external one, SCrewed down to the window jamb and connected to 120/240 volts internally. They resemble a window A/C, but the rads are below the window level and are wider and less deep. I am getting a few next year. This is one of many. https://www.greenbuildingadvisor.com/article/startup-promises-window-mounted-heat-pump-by-next-year https://www.greenbuildingadvisor.com/article/startup-promise...